Across the country there are huge pockets of fast-emptying countryside. Some analyses of economic and social distress in those areas suggest America's own “third world” is in the making. Although the label “rural” applies to such a variety of geographic and economic settings that no sweeping characterization or prophecy fits them all, for the most part the nation's rural areas are older and poorer than urbanized America. And they are getting more so.

The 1990 census is expected to confirm something demographers have been detecting for several years: The rural migration to urban America is back on course, resuming a historical pattern that was merely interrupted in the 1970s. While experts differ on the size of the migration, they agree that it has meant trouble for many of the 60 million people—nearly a quarter of the nation's total population—who live outside the 284 officially designated metropolitan areas.

Calvin L. Beale, a senior demographer with the Department of Agriculture, believes fewer people left the countryside in the past decade than in the 1950s or '60s, but that the later departures may have been the worst blow of all in many struggling communities. “It's a critical mass they are losing,” he says. “The sense of community is impaired.”